The present invention relates to an equipment for the surface emission of infrared radiation, such as used, for example, for drying and/or curing paints, mastics, lacquers, glues, etc., or for preheating a plastic prior to thermoforming.
By way of example, although not exclusively, the invention relates to installations of the tunnel type comprising a thermally insulated wall forming a tunnel which is elongate in a direction of residence or travel of at least one object to be treated with said infrared radiation. These installations generally comprise a number of unitary surface emission equipments or modules, each arranged with respect to and in the thermally insulated wall, in such a way that their respective faces emitting the infrared radiation face toward the inside of the tunnel. Each surface emission equipment item or module comprises one or more surface emission devices. Each said device comprises a seat of catalytic combustion comprising a catalytic combustion wall made of refractory material, permeable in its thickness and suited to the passage of a mixture for burning (fuel gas, for example natural gas, plus oxidizing gas, for example air) from its upstream face to its downstream face emitting said infrared radiation and discharging the flue gases. The developed interior surface of the catalytic combustion wall is coated with a combustion catalyzing material, for example platinum and/or palladium. The seat of combustion comprises an upstream chamber supplied, on one side, with mixture for burning and closed, on the other side, by the catalytic combustion wall.
For an installation such as the one defined above, the object of the present invention is various arrangements collaborating with one another with a view tO recuperating and consuming at least a substantial proportion of the residual heat present in the flue gases of each, or of the various, unitary, surface emission equipment item(s).
According to the present invention, the surface emission equipment comprises, in combination, the following characteristics:
the surface emission device comprises a box in which the seat of catalytic combustion is arranged at least in part, and in which there is formed an opening facing the downstream face of the catalytic combustion wall;
at least one window pane made of transparent ceramic material is mounted, for example in the box of the surface emission device, so as to form, with the seat of catalytic combustion, a circuit for discharging the flue gases leaving via the downstream face of said surface emission device;
and the equipment comprises a secondary surface emission metal sheet forming a flat circulation channel for the flue gases and communicating on the one side with the circuit for discharging the flue gases of the surface emission device and, on the other side with at least one outlet pipe for transferring the flue gases out of the equipment.
By virtue of these arrangements, the object or objects to be treated receive secondary thermal radiation which adds to the main infrared radiation, emitted by an equipment item according to the invention.